Effect of nitrogen sources on fruit characteristics and seed physiological quality of Physalis angulata L.

Abstract

ABSTRACT Choosing an appropriate nitrogen source is of utmost importance, since it affects the plant development and fruit and seed yield. This study aimed to evaluate the quality of Physalis angulata fruits and seeds obtained from plants grown in a hydroponic system, under different concentrations of nitrate and ammonium. The treatments consisted of four NO3-:NH4+ ratios (100:0, 75:25, 50:50 and 25:75). After full grown, the fruits were collected for biometric and chemical analyses, and seeds were removed for the germination test. The germination test was conducted in a germination chamber and the parameters evaluated were the germination rate, mean germination time, speed, germination uniformity coefficient and relative frequency. Fruits with lower weight and diameter were obtained at doses above 50 % of ammonium; however, there was an increase for ºBrix and soluble solids/titratable acidity ratio. Such dosage also reduced the rate, speed and uniformity of germination. The combined use of nitrogen sources (50:50 of NO3-:NH4+) is recommended, because it produces larger and sweeter fruits with vigorous seeds.